Safety and Performance Using Legion™ CR Oxinium and CoCr Femoral Implants Combined With Legion™/Genesis™ II XLPE High Flex Tibial Inserts

Inclusion Criteria: 1. Subject received primary TKA with the Legion™ CR Femoral Implant (either Oxinium or CoCr) with Legion™/Genesis™ II XLPE Hi-flex Tibial Insert, due to degenerative joint disease (primary diagnosis of osteoarthritis, post-traumatic arthritis, degenerative arthritis, or rheumatoid arthritis). 2. Subject received primary TKA between 24 and 66 months prior to the time of consent. 3. Subject agrees to consent and to follow the study visit schedule (as defined in the study protocol and informed consent form) by signing the IRB/EC approved informed consent form. 4. Subject must be available through ten (10) years postoperative follow-up. Exclusion Criteria: 1. Subject had Body Mass Index (BMI) \> 40 at time of surgery. 2. Subject received the Legion™ CR Femoral Implant with Legion™/Genesis™ II XLPE Hi-flex Tibial Insert as a revision surgery. 3. Subject has a condition that may interfere with the TKA survival or outcome (e.g. Paget's or Charcot's disease, vascular insufficiency, muscular atrophy, uncontrolled diabetes, moderate to severe renal insufficiency or neuromuscular disease). 4. Subject has a known allergy to one or more of its components of the study device. 5. Subject, in the opinion of the Principal Investigator (PI), has an emotional or neurological condition that would pre-empt their ability or willingness to participate in the study including mental illness, mental retardation, drug or alcohol abuse. 6. Subject is entered in another drug, biologic, or device study or has been treated with an investigational product in the past 30 days. 7. Subject is known to be at risk for loss to follow-up, or failure to return for scheduled visits.